Provided is a method for extracting a 1,5-pentanediamine from a solution system containing a 1,5-pentanediamine salt. The method comprises adding to the solution system an insoluble basic substance to form a solution system containing free 1,5-pentanediamine. The provided method has high applicability, is easy to use, and is environmentally-friendly, significantly lowering raw material costs and operating costs for the entire manufacturing process. The method achieves a high recovery rate for pentanediamine, and is more suitable for industrial-scale production.